This is all they’ll send me, not good. A fourth gear pull showing the dyno shutting down at 125 mph. As I wrote I saw during several 3rd gear pulls Revo 351, APR 328 HP. It was 87F in the dyno bay.
Yes sir, if it’s got the range to make it to the strip?
If the 300+ mile range can’t make it to the strip how the hell does your gas car make it to the strip? There are superchargers pretty close to MOST drag strips anyway if not fast chargers at the very least.
Although comparing a car that is double the price of the S4 makes no sense, may want to be talking about an RS7 if we are comparing apples to apples.
I would be very interested in seeing a back to back comparison at the strip specifically on a warmer day. With that said APR and GIAC are still the kings when it comes to the strip.
I remember discussing this kind of stuff with Jim when we were doing the thread on 1/4 short shifting.
Found a thread (by HRE so take it for what it’s worth) discussing this very topic here: http://www.audizine.com/forum/showthread.php/467909-Dyno-Runs-The-effects-of-wheel-tire-weights-on-wheel-horsepower
Here is their OP:
[quote]Test:
Davenport Motorsports (www.davenportmotorsports.com) of Canada, wanted to see the dyno effects of running different wheels on cars. They took a factory 2012 Camaro SS and ran 3 dyno runs. They ran the first run with a set of aftermarket wheels, the 2nd run with a set of stock factory wheels and the 3rd run with a set of HRE P45S wheels, all in 20” sizes.
These results highlight the effects of rotational inertia on drive-train losses (the hp lost between the engine crank and the ground). Wheels and tires contribute to drive-train losses as energy is used to spin up the wheels (and decelerate the wheels under braking). From the dyno chart you can see the effect of replacing factory wheels with lighter HRE wheels and see the negative effects of installing heavier aftermarket wheels.
Results:
- (Blue curve) Factory wheels: 20”x9.0” with Pirelli 275/40-20 tires weighing 68 lbs combined per rear wheel. – Max hp: 371 hp, Max Torque: 375 ftlbs - (Baseline)
- (Red curve) Aftermarket wheels: 20”x9.0” with Pirelli 275/40-20 tires weighing 72 lbs combined per rear wheel – Max hp: 369 hp, Max Torque: 373 ftlbs - (A [-] loss of 2 hp and 2 ftlbs)
- (Green curve) HRE wheels: 20”x11.0” with Nitto 315/35-20 tires weighing 60 lbs combined per rear wheel – Max hp: 380hp, Max Torque: 384 ftlbs - (A [+] gain of 8 hp and 9 ftlbs and that is running a 2” wider wheel/tire combo)
Conclusion:
The engine obviously still cranks out the same amount of hp and torque, the lighter HREs simply waste less of it before it gets to the ground. Also interesting to note is that the gains are not just peak gains, but gains across the entire rev range. If they had done a braking test, we would have seen similar results as the rotational inertia effects also have a significant effect on how much energy is used to stop the wheel/tire combo vs. stopping the car. We talk about these effects all the time and focus on designing lightweight wheels with low rotational inertia, but it isn’t every day that you get to see real hard data showing the true effects.
http://farm8.staticflickr.com/7027/6757639011_6f815e24be_b.jpg
[/quote]
Someone there (vwong) claims that dynopack dynos take wheel weight into account. So this might be different, quote here: http://www.audizine.com/forum/showthread.php/467909-Dyno-Runs-The-effects-of-wheel-tire-weights-on-wheel-horsepower?p=7220919&viewfull=1#post7220919
Gonna have to agree with skywagon with this, might be great if you live in Silicon valley, and can charge the car no matter where you go (work, grocery store, S/C station nearby), but in general, those stations are really sparse
I’ve seen the Tesla get about 1/3 the mileage when driving spiritedly, and it charges at a laughable 15 miles/hr on a 240 volt outlet. An EV would be awesome if you lived 15 min from work and had another car for longer trips, but it’ll be a while till these cars become more than novelty items to rich guys. I do really like the idea of a plug-in-hybrid though, best of both worlds IMO.
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the 2 wheels that are the same size and with the same tires posted virtually identical results. 1.8 hp on a dyno is identical when you factor in error allowance. Also the difference was 0.0 from 0 to 4800 RPMs…and the lines again meet a few more times towards redline (5200, 5600). This is despite dropping 8 pounds of rotating mass. Significant.
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the 3rd set with the ‘gain’ also have totally different tires, with massively different sizes, which will influence a lot of things, namely how the car loads up the dyno and puts traction down
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they did 1 pass on each? That will produce pretty jagged results. Why not make 3 passes on each setup, then smoothe each of the 3 out?
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if I were sceptical, I would point out that there were 10 run files created…and they showed 1 for each set of wheels. Interesting that. Was this the set that best made the case for selling $6,000 wheels/ Considering the test was done by guys who sell $6,000 wheels, questions like this need to be asked.
Someone there (vwong) claims that dynopack dynos take wheel weight into account. So this might be different, quote here: http://www.audizine.com/forum/showthread.php/467909-Dyno-Runs-The-effects-of-wheel-tire-weights-on-wheel-horsepower?p=7220919&viewfull=1#post7220919
[/quote]
Not to mention the performance drops off a lot at higher speeds. The torque near 0 is incredible, but without a transmission, the motors lose a lot of steam.
Concur. Primetime, I’m going out of town for 12 days, unexpected road trip. Logging will have to wait until I get back. My apologies, thanks for your patience.
I’ll share some logs I have for Revo here. I covered some of this in my dyno thread, but I’m still pretty torn on what to think about the Revo stage 2 tune and logs. It’s a nice smooth curve; probably the smoothest I have seen on a dyno, but there is absolutely no knock/timing pull reported even as IAT’s get up to 80 degrees C. Absolute timing gets up to 23 degrees, which combined with the high IAT’s, and no knock/timing pull, seems somewhere between odd and dangerous. Thoughts?
Dyno:
http://i570.photobucket.com/albums/ss146/jran76/File-11-10-2014-01-36-41-page-1_zps390384f3.jpg
1st Pass:
http://i570.photobucket.com/albums/ss146/jran76/Revo1stPass_zps63592167.jpg
2nd Pass:
http://i570.photobucket.com/albums/ss146/jran76/Revo2ndPass_zps78a19164.jpg
3rd Pass:
http://i570.photobucket.com/albums/ss146/jran76/Revo3rdPass_zps786c4b5f.jpg
Well, Revo (Jeff F.) did respond on Vendorzine:
[i][b]Here is a response from Robin, one of our engineers who works on the Siemens projects:
The numbers would be higher if the car was allowed to rev-- with the DSG flash, 7000-7100RPM is possible and the car will continue to make peak power the higher it revs. We usually see another 15-20HP when the car is at redline vs when the standard DSG file changes gear. These dyno charts don’t show the actual benefit of having the DSG controller flashed.
To properly interpret the data, you have to have an understanding of how the SIMOS ECU works. It has three different timing tables that it will interpolate from to arrive at a final ignition timing value after passing through many factors for cat temp, intake air temp, load, etc etc… Precise calibration of these tables is necessary to achieve a smooth and strong timing curve. The fact that the car wasn’t pulling anything out is GOOD, that means it’s running happily and not having to make many adjustments. After 4-5 pulls, it will have adapted to the load and conditions on the dyno and would have started pulling a degree or two out now and then. We usually find the cars make peak power after a few pulls, not on the first pull like most cars. If you ask for too much timing, the car will actually make much less than is actually achievable. Best results are achieved with tables that are actually conservative! The stock strategy is EXTREMELY conservative with how it responds to knock. When it picks up a little bit, it will pull out MUCH more timing than is necessary, creating higher EGTs and a sloppy curve. We modify the factory strategy in a way that keeps the factory safety routines in place, but changes the response loop so it will pull less timing and add it back in quicker. It’s not “turning off the knock sensors” as posted above. Obviously we don’t recommend this, but the car can still remove enough timing to safely run the 100 program on 93, or the 93 program on 91. The stronger timing curve helps torque, power, and keeps EGTs under control. A word that keeps getting thrown around in this thread is “desensitizing”… that’s not what’s occurring, we’re simply changing the OEM strategy to allow the car to run as we desire. The OEM engineers who tuned this car weren’t looking for peak power, or pretty curves. They were given a power level, CO2 and NOx emissions limits, and fuel consumption limits and they had to make everything work in a package that has to satisfy everybody. This is why we are able to make such good gains on these cars, because of the highly conservative factory logic and the fact that the motor runs at about 70HP off of it’s potential. From a reliability standpoint, we have thousands of 3.0Ts running all over the world in various platforms without any reliability issues.
The factory fuel strategy in the 3.0T is modified as well with our code. The stock car will run fairly lean until crossing a modeled EGT threshold of about 900C, then will enrich heavily at that point to cool things off. If this strategy isn’t modified, the fueling will be inconsistent. The car is always in a targeted lambda closed loop mode, it never runs “open loop” as stated in this thread. The ECU targets a specific lambda based on mass air flow and RPM. We go richer earlier, to keep EGTs in control and allow for more ignition timing. In this case, the Revo car started to enrich at about 6500rpm probably because it was starting to get hot. On the street this will usually not happen until 5th gear or so, but it can happen sooner on the dyno with less airflow and different loading. Keep in mind a tailpipe wideband sensor as used on this dyno will read about half a point leaner than the car is actually running due to the catalyst. The black smoke noticed on the other cars is most likely a result of knock. The car will enrich under knock to try and cure it, and it’s usually visible as small puffs of smoke under heavy load.[/b][/i]
I really liked his reply. Unfortunately, as he is the professional and I am the client, I have to trust this and hope they have honestly found some magic formula.
+1 Revo is solid. Tempted to put 106 octane in and dyno it.
Do it. DO IT!
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Sigh… How about another visit to the strip?
Drag racing is for American muscle, remember? ;D
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I will have a web redemption. One of these Wednesday nights at Sonoma. Been busy getting to know the Boxster.
Ditch the boxster go run the s4
The revo car’s logs show it’s running 3-4’ more timing than my car did stock at the same RPM/IAT and I had stock boost. http://datazap.me/u/boosteasy/s5-stock-84f?log=0&data=2-3-5-8&zoom=694-742
If my stock car is a benchmark for normal, it seems the Revo car was either running a few more points of octane than admitted or the tune is configured so that it’s acting like it does.
boost, agreed… those timing values are close to what I see on the APR 100 tune with Sunoco GT260 and I’ll still see some pull if IAT’s get up there like these are… I guess it’s a little lower than the 35-40 degrees we saw on the “old” 100 file they put out… Hopefully, it doesn’t end the same way…
In the end like Jeff said I’m not a tuner so hopefully it’s safe and they have many happy customers…